Fire crews rush to protect Yosemite's sequoias

Firefighters battling to safeguard ancient sequoias as blaze grows

Updated 5:33 pm, Tuesday, August 27, 2013

The Rim Fire burns near Yosemite National Park. At 284 square miles, it is the seventh-largest wildfire in California history.

The Rim Fire burns near Yosemite National Park. At 284 square miles, it is the seventh-largest wildfire in California history.

Photo: Jae C. Hong, Associated Press

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Sacramento River Fire District Capt. Jerry Winters rests at base camp Monday before the start of the night shift.

Sacramento River Fire District Capt. Jerry Winters rests at base camp Monday before the start of the night shift.

Photo: Paul Kitagaki Jr., McClatchy-Tribune News Service

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File — Firefighters are racing to save these Giant sequoias in Yosemite National Park.

File — Firefighters are racing to save these Giant sequoias in Yosemite National Park.

Photo: Getty Images, File

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File — Firefighters are racing to save this log cabin museum among a grove of giant sequoias, looking up in Yosemite National Park.

File — Firefighters are racing to save this log cabin museum among a grove of giant sequoias, looking up in Yosemite National Park.

Photo: Anders Blomqvist, File

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File — Firefighters are racing to save these Giant sequoias in Yosemite National Park.

File — Firefighters are racing to save these Giant sequoias in Yosemite National Park.

Photo: Pierre Leclerc Photography, File

Fire crews rush to protect Yosemite's sequoias

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Yosemite National Park's giant sequoias have withstood millennia of hardship, from bugs to fungal rot to the swing of the ax. Sequoias - the largest trees on Earth - even embrace wildfire as a tool for survival.

But park officials monitoring the huge Rim Fire in the central Sierra say the old giants may have met their match.

The blaze is rapidly approaching two of Yosemite's three renowned sequoia sites, the Tuolumne and Merced groves, and firefighters are doing all they can to give the redwoods a leg up should fire strike.

"Normally we would say that fire is good for a sequoia grove. But a fire that is burning too hot is not healthy for any tree," said Tom Medema, Yosemite's chief of interpretation and education.

The Rim Fire, which started Aug. 17 in the Stanislaus National Forest and has since crept into the national park, is fueled by bone-dry forest and is spreading unusually fast through the treetops. Medema said strict fire suppression policies of the past have left a surplus of fuel to burn and, as a result, made the Rim Fire burn with more intensity and heat.

"The types of fires that normally go through these groves are lower-intensity ground fires," Medema said. "That's a more natural kind of fire."

To protect the ancient sequoias, firefighters are dousing trees at the two groves with sprinklers and cutting firebreaks to prepare them for flames.

Fire continues to grow

By Tuesday afternoon, the Rim Fire had swelled to 284 square miles, fire officials said, making it the seventh-largest wildfire in California history.

Nearly 3,800 firefighters were battling the fire, mostly on two fronts: on the east side, where 42,000 acres of Yosemite had burned - or about 6 percent of the park - and on the northwest side, where a handful of foothill communities stand in its path.

"The weather is just not cooperating with us," said Lynn Tolmachoff, a spokeswoman for the California Department of Forestry and Fire Protection, citing gusty winds and warm temperatures.

Fortunately, she said, the advance of flames to the northwest toward Tuolumne City, Twain Harte and Ponderosa Hills had slowed. Many residents in the area remained under an evacuation advisory.

The fire had burned 31 residences and 80 other structures, with much of the damage coming at the city of Berkeley's Tuolumne Camp near Groveland, west of Yosemite.

More than 4,500 residences remained threatened, and officials said the cost of the fight had risen to $27 million. The cause is not known.

The blaze remained a little more than four miles from the sequoia groves late Tuesday.

Saving history

At Merced Grove, crews are also trying to safeguard a nearly century-old cabin that was the site of an early entrance station - when visitors toured the park in horse-drawn carriages.

The log structure is being wrapped in fire-resistant material.

The giant sequoias, some of which date back more than 2,000 years, have their own retardant: a rust-colored, fire-resistant bark that can grow several feet thick. While the tree trunks repel flames, the cones absorb the heat to disperse seeds needed for reproduction.

Giant sequoias are not to be confused with their coastal brethren, commonly called coast redwoods, which grow taller but are much less massive.

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